Load remote images

When loading an image by filename and by hash fails, try to interpret
the filename as URL and download the image.

Signed-off-by: Robert C. Helling <helling@atdotde.de>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

dives/test43.xml

@@ -0,0 +1,29 @@
+<divelog program='subsurface' version='3'>
+<settings>
+<divecomputerid model='Suunto Vyper' deviceid='7fffffff' serial='00522075' firmware='0.0.33'/>
+<divecomputerid model='Suunto Vyper' deviceid='e9237b0a' nickname='Suunto Vyper (e9237b0a)'/>
+  <autogroup state='1' />
+</settings>
+<divesites>
+<site uuid='47b3e28c' gps='47.934500 11.334500'/>
+</divesites>
+<dives>
+<trip date='2012-01-08' time='15:30:03'>
+<dive number='1' divesiteid='47b3e28c' date='2012-01-08' time='15:30:03' duration='46:06 min'>
+  <notes>This is a dive with an image on a remote server.</notes>
+  <cylinder size='24.0 l' workpressure='232.0 bar' description='D12 232 bar' />
+  <divecomputer model='manually added dive' date='2014-01-09' time='14:22:03'>
+  <depth max='15.0 m' mean='13.698 m' />
+  <sample time='0:00 min' depth='0.0 m' />
+  <sample time='0:50 min' depth='15.0 m' />
+  <sample time='1:00 min' depth='15.0 m' />
+  <sample time='40:00 min' depth='15.0 m' />
+  <sample time='42:00 min' depth='5.0 m' />
+  <sample time='45:00 min' depth='5.0 m' />
+  <sample time='46:06 min' depth='0.0 m' />
+  </divecomputer>
+  <picture filename='http://euve10195.vserver.de/~robert/wreck.jpg' offset='+21:01 min' />
+</dive>
+</trip>
+</dives>
+</divelog>

qt-ui/divepicturewidget.cpp

@@ -2,21 +2,34 @@
 #include "metrics.h"
 #include "dive.h"
 #include "divelist.h"
+#include <unistd.h>
 #include <QtConcurrentMap>
 #include <QtConcurrentRun>
 #include <QFuture>
 #include <QDir>
 #include <QCryptographicHash>
+#include <QNetworkAccessManager>
+#include <QNetworkReply>
 #include <mainwindow.h>
 #include <qthelper.h>
+#include <QStandardPaths>
+
+void loadPicuture(struct picture *picture)
+{
+	ImageDownloader download(picture);
+	download.load();
+}
 
 SHashedImage::SHashedImage(struct picture *picture) : QImage(picture->filename)
 {
 	if (isNull()) {
 		// Hash lookup.
 		load(fileFromHash(picture->hash));
-		if (!isNull())
+		if (!isNull()) {
 			QtConcurrent::run(updateHash, picture);
+		} else {
+			QtConcurrent::run(loadPicuture, picture);
+		}
 	} else {
 		QByteArray hash = hashFile(QString(picture->filename));
 		free(picture->hash);
@@ -24,6 +37,45 @@ SHashedImage::SHashedImage(struct picture *picture) : QImage(picture->filename)
 	}
 }
 
+ImageDownloader::ImageDownloader(struct picture *pic)
+{
+	picture = pic;
+}
+
+void ImageDownloader::load(){
+	QUrl url(picture->filename);
+	if (url.isValid()) {
+		QEventLoop loop;
+		QNetworkRequest request(url);
+		connect(&manager, SIGNAL(finished(QNetworkReply *)), this, SLOT(saveImage(QNetworkReply *)));
+		QNetworkReply *reply = manager.get(request);
+		while (reply->isRunning()) {
+			loop.processEvents();
+			sleep(1);
+		}
+	}
+
+}
+
+void ImageDownloader::saveImage(QNetworkReply *reply)
+{
+	QByteArray imageData = reply->readAll();
+	QCryptographicHash hash(QCryptographicHash::Sha1);
+	hash.addData(imageData);
+	QFile imageFile(QStandardPaths::standardLocations(QStandardPaths::CacheLocation).first().append("/").append(hash.result().toHex()));
+	if (imageFile.open(QIODevice::WriteOnly)) {
+		QDataStream stream(&imageFile);
+		stream.writeRawData(imageData.data(), imageData.length());
+		imageFile.waitForBytesWritten(-1);
+		imageFile.close();
+		add_hash(imageFile.fileName(), hash.result());
+		learnHash(picture, hash.result());
+		DivePictureModel::instance()->updateDivePictures();
+	}
+	reply->manager()->deleteLater();
+	reply->deleteLater();
+}
+
 DivePictureModel *DivePictureModel::instance()
 {
 	static DivePictureModel *self = new DivePictureModel();
@@ -47,7 +99,9 @@ SPixmap scaleImages(picturepointer picture)
 		ret.second = cache.value(picture->filename);
 	} else {
 		int dim = defaultIconMetrics().sz_pic;
-		QImage p = SHashedImage(picture).scaled(dim, dim, Qt::KeepAspectRatio);
+		QImage p = SHashedImage(picture);
+		if(!p.isNull())
+			p = p.scaled(dim, dim, Qt::KeepAspectRatio);
 			cache.insert(picture->filename, p);
 		ret.second = p;
 	}

qt-ui/divepicturewidget.h

@@ -5,6 +5,7 @@
 #include <QListView>
 #include <QThread>
 #include <QFuture>
+#include <QNetworkReply>
 
 typedef QPair<QString, QByteArray> SHashedFilename;
 
@@ -18,6 +19,18 @@ public:
 	SHashedImage(struct picture *picture);
 };
 
+class ImageDownloader : public QObject {
+	Q_OBJECT;
+public:
+	ImageDownloader(struct picture *picture);
+	void load();
+private:
+	struct picture *picture;
+	QNetworkAccessManager manager;
+private slots:
+	void saveImage(QNetworkReply *reply);
+};
+
 class DivePictureModel : public QAbstractTableModel {
 	Q_OBJECT
 public:

qthelper.cpp

@@ -850,6 +850,13 @@ QByteArray hashFile(const QString filename)
 	return hash.result();
 }
 
+void learnHash(struct picture *picture, QByteArray hash)
+{
+	free(picture->hash);
+	hashOf[QString(picture->filename)] = hash;
+	picture->hash = strdup(hash.toHex());
+}
+
 QString localFilePath(const QString originalFilename)
 {
 	return localFilenameOf[hashOf[originalFilename]];

qthelper.h

@@ -25,4 +25,5 @@ void learnImages(const QDir dir, int max_recursions, bool recursed);
 void add_hash(const QString filename, QByteArray hash);
 QString localFilePath(const QString originalFilename);
 QString fileFromHash(char *hash);
+void learnHash(struct picture *picture, QByteArray hash);
 #endif // QTHELPER_H